I'm 192cm, with a 89cm inside leg..(i.e. 6'3 1/2 height..).
Am considering a GOOD deal on a Bianchi Via Nirone in a 59cm, but the dealer tells me it's too short a frame...
Do I need a 61cm?
I do mostly short 10-30mile runs (as fast as I can...), as with two small kids 4-5 hour trips is now on the cards (much).

Also:
This is a Bianchi Via Nirone with Campy Veloce (want an all Italian bike), the alternative is slightly more for an Impulso, also to get a 61cm should I need it.

Via Nirone or Impulso ?? I take it the Impulso is very very similar but being slightly racier in the geometry of the two...

I don't think the leg length is an issue at all; it's clearly no problem making up the 28-30cm from the top of the seat tube to your proper seat height with a commonly available 35cm seat post. The bigger issue is your reach from seat to bars. If you can get into your preferred or desired riding position on the 59, I'd say it fits. If not, and you need more reach, then try the 61.

Without seeing your riding position (or knowing arm length) it's impossible to do more than guess, but looking at the geometry charts on both those models, they look identical, so that may make deciding easier.

Thanks!
Turns out I'm more 90cm + inseam, so maybe the 59cm is out of the question....

Yes, that changes things, and especially since the top tube lengths are only 10mm apart, which should allow easy stem adjustment for reach either way, presuming the stock is a 110 or 120mm stem; no problem dropping back 10-20mm if needed. And don't forget, although it is a bit more expensive than a stem swap, that handlebars have different reaches and drops, so you can tune there as well.

I like the Impulso in the black/grey color scheme; you could add some celeste accents nicely, for that classic touch!